A representative scheduler in the related art may be a proportional fair (PF) scheduler. The PF scheduler calculates a selection reference value on the basis of an instantaneous channel with respect to each user for each transmission unit time, and selects a user on the basis of the calculated selection reference value. The PF scheduler has the property of alternately selecting all users in an environment in which a user's instantaneous channel rate is not greatly changed.
As a performance index of a wireless network, there is a perceived throughput. The perceived throughput is a value that is obtained by dividing a file or a packet having a finite size B by time W taken to completely transmit the file or the packet. When using an application, a user can easily perceive the throughput performance. The perceived throughput is defined in the long term evolution (LTE) standard document TS 36.814, and may be expressed as in Equation 1.
                              R          p                =                  B          W                                    Equation        ⁢                                  ⁢        1            
Here, the file or the packet having the finite size may be the file or the packet having a very small data unit or the file or the packet having a very large data unit within the limit that can be transmitted by a communication system. For convenience, in the present disclosure, the term “file” or “packet” is used, but is not limited thereto. All data sets that can be discriminated from other data sets may correspond to the term. For example, the term may include all typical packet units that are transmitted in LTE, wideband code division multiple access (WCDMA), worldwide interoperability for microwave access (WiMAX), WiFi, and the like.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.